Trimble SCS900 Hydro updates

Patch to SCS900 v2.71 version.

þ
The release of SCS900 v2.71(build
number 94) has a bug which does not load the external application
DLL thus preventing the SonarMite application working. This
has been fixed by Trimble and released as an update patch in SCS900 (v2.71 build
number 95 or later).

SonarMite application software (SCS900 v2.5 version).

þ
The SonarMite application software has been updated to provide the time stamped
data form required by the updated SCS900 application, this includes updated
'pipe' and 'socket' processes for passing data between applications. The
SonarMite application has been tied to the following operating systems ...

PC Version - Windows Vista, TabletPC and Windows 7

Mobile Version - Trimble TSC2 Windows Mobile 6.0

þ To avoid the
problems associated with applications working in forthcoming updates to these
operating systems the applications have been compiled as 'standalone' with no
dependence on version specific extensions to the environment.

þ The Trimble ACU/TCU
versions have been dropped as the WinCe Operating System requires a specific
compiler and software developers kit which does not warrant the low demand and
high level of support required.

þ The properties
dialog box does not show the settings used by the HPR sensor but includes prime
sonar setting control settings …

QA control - A slider control has been added so the user can set
the acceptance level for the QA value between normal and highest value. The
highest will filter out all but the very best shots based on QA

Speed of Sound - The user can set the sound velocity value between
1400-1600m/sec, the default setting being 1500 m/sec.

Socket Number – The socket number used to transmit the data between
applications (PC version only), default updated to #1600 to avoid confusion
with earlier SCS900 versions.

Latency Calculation - The user can enable/disable the Latency
correction algorithm within the SCS900 extension module, unless the system is
using SCS900 to measure positions this function is inoperative.

SCS900 Extension Module DLL

þ Depth Time
(latency) adjustment

The SCS900 extension dll is called by the main
application and passed a position with a timestamp, the SonarMite extension dll
adjusts the depth based on the depth timestamps to suit the timing of the
position, this calculated depth is then subtracted from the current position Z
value (or height) and returned to the main SCS900 application.

þ Estimation
of delay from Ping to Depth Timestamp

As the extension dll receives its data via serial
transmission and timestamps it on reception of the Linefeed character, the
calculation of the delay from the depth 'start ping' time and subtracts it from
the applied depth timestamp.

þ Retention
of raw data

CustomDataField 1 = Depth subtracted from current Z
value

CustomDataField 2 = Current Depth QA value

CustomDataField 3 = Time between Position and Depth
(milliseconds).

These values can be used to reconstitute the original data
if required and also estimate the applied time shift and depth QA value.

þ Simulation
Mode

The simulation mode in menu DEVICE/TEST DATA/ has been
updated to send a timestamp with the simulated depth message. This helps
configure or demonstrate the system without the need for a physical SonarMite to
be connected.

þþModifications to QA
filter settings

It was found the QA settings were previously set a little
tight for reliable collection of data. The settings were made on the basis
that reliable data would be required under the following conditions ...

SCS900 would be used in
turbid water conditions in a construction environment.

It would be unlikely the
software would be used in depths greater than 25m.

As there were several situations in which this was not the
case and data was filtered out the QA filter slider has been modified for a
wider range of operation and that a windows error beep is also sounded if data
fails to pass the filter settings. Previously the slider filter point ranged
from QA values 80 to 110, the new settings are set for a range of 40 through
to 100.

þþExplanation of the QA value

The QA value is a numeric representation of the inverse gain
applied to the sonar transmission in order to maintain minimum beamwidth. In
simple terms more power has to be applied in bad conditions to achieve the
same return. The value of this number is complex and depends on several
parameters ...

Turbidity - Quality of water in the column
under the transducer.

Relection – The ‘hardness’ of the bottom
surface.

Sound Velocity – The transmission speed of
sound in water.

Depth – The total depth the sound has to
travel through the water.

þþAuto enumeration of
COM: ports.

The PC software has been modified to detect and auto enumerate
com ports when making a serial connection to the SonarMite. This gets over the
technical problems with port numbers greater than 10 in Winows Vista and
Windows 7. The PDA version is still limited to ports COM1 to COM10.